The invention described herein was made in the course of, or under, a contract with the United States Atomic Energy Commission, and pertains generally to ultrasonic transducers and more specifically to ultrasonic transducers designed to monitor gas entrainment.
The theory and application of acoustical techniques to quantify voids or bubbles in liquids are rather well known in the art. Several unique techniques exist for this purpose. A transmission technique employs a measure of the total attenuation of an ultrasonic signal as it travels through the liquid being monitored. A scattering technique employs a measure of the degree of scattering reflected from voids passing through an acoustical beam. A third speed of sound technique measures the change in transmission times due to the differences in the speed of sound in voids as compared to liquids.
While these techniques have been successful in monitoring the presence of voids and quantifying them within the path of the acoustic beam, the present state of the art has not advanced to the stage where the total volume of liquid within a container can be monitored without employing an exhaustive number of transducers around the periphery of the liquid enclosure. Generally, a transducer is positioned at one location on the fluid container surface and a reflector is diametrically supported on the opposite container surface. The volume of liquid within the path of the acoustic beam is then monitored and the results extrapolated to cover the entire volume of liquid. While the resulting data has been satisfactory for most applications, precision measurements have not been able to be accommodated.
An accurate measure of the total volume of liquid would expand the capabilities of ultrasonics to more versatile applications in nuclear reactor systems such as sodium cooled breeder reactors. Such systems could then be employed to detect voids in the sodium coolant resulting from the release of fission gas during a fuel element failure; evidencing the fault.
Accordingly, a new acoustical device is desired having the capabilities of accurately measuring an entire volume of liquid enclosed within, or transported through a container.